electricity definitions

current flow which consists of charges that continually change direction.

these oscillations usually occur at a set frequency

alternating current

a device connected in series with a component to measure the current that flows through it

ammeter?

a safety device that cuts off the power supply if a surge of current passes through it.

circuit breakers can be reset and are quicker acting than fuses.

circuit breaker

a component that only allows current to flow through in the forward direction.

they have very large resistances in the reserve direction

diode

current flow consisting of charges flowing in a single direction.

batteries and cells provide direct current

direct current?

the removal of excess charge by providing a low resistance path for electrons to flow through

earthing

the green and yellow striped safety wire connected to metal casing that prevents an appliance from becoming live

earth wire

a safety decide consisting of a thin metal filament that melts and cuts off the power supply if there is a surge in the current. fuses are connected to the live wire.

fuse?

the brown coloured wire that carries the alternating current from the supply in a main power supply

live wire

the blue coloured wire that completes the circuit in a mains power supply

neutral wire

a device that is connected in parallel with a component to measure the potential difference across it.

voltmeter